Compaq Presario Notebook 1200XL-111

I have the above indicated notebook and the system board is bad. Onboard memory is shot and system keeps locking up. I would like to upgrade it to possibly a P4 or AMD XP. It has a AMD K6 2 500MhZ processor. I have contacted Compaq/HP and they quoted me 400 for the same system board. Any body have any suggestions as to what I can do besides using it for an anchor. Are there any vendors out there that can help?